I'd assume they would need to tackle the infastructure of a degrading hill in topography would dictate for a large project of that scale to take place; with it affecting that area directly, that they would have to close SES and Animal Actors regardless: so they can tear down and reduce the risk of collapse.
My question is on Luigis, P.Q. Butterfats, and Duff Gardens. How long they last closed, how they change after they open.